填空题: <br /> <img src="http://www.weimei168.com/uploads/202208/20130108160836193619.jpg" alt="" border="0" /> <br /> 外力做功是__________J，电势能增加是__________J． <br /> <img src="http://www.weimei168.com/uploads/202208/20130108160874137413.jpg" alt="" border="0" /> <br />